OTTAWA -- Jamie Oliver, Britain's celebrity chef, has thrown down the gauntlet -- or maybe it's an oven mitt -- to Canadian politicians to join his international campaign for mandatory diet education in rich countries.

The popular chef, television star and best-selling author says it is time for Canadian politicians to do something about their country's number one killer: diet-related disease.

"The biggest killer in your country is diet-related disease. It's not guns, it's not armed robbery," Oliver said in an exclusive interview from Sydney, Australia, where he launched a global campaign this week urging G20 countries to make food education mandatory in schools.

"When it has a dramatic cost to public health, which it does in Canada ... you really need to do something much more long term, much more strategic."

Oliver is well known for his international advocacy for healthy food in schools, but he's upping the ante with his G20 campaign.

He's aiming for millions of signatures worldwide, and is off to a good start: an online petition through the website Change.org attracted 160,000 in the first 24 hours. Oliver cooked for G20 leaders in London at their 2009 summit.

Oliver said he's not political, but the issue of healthy food has been a politically charged one in Canada.

Recent images showed Rankin Inlet residents foraging for food in a dump, while the United Nations food envoy criticized Canada two years ago for not ensuring healthy food reached vulnerable populations, including aboriginals.

"It's about Canadian politicians looking after every child, whether they're middle class, whether they're from rich communities, whether they're poor or whether they're in the far limbs of the country, and whatever ethnic backgrounds," said Oliver.

This week, the Canadian Task Force on Preventive Health Care, for the first time in more than two decades, called on doctors to monitor the growth of their young patients on an ongoing basis.

It recommended that doctors refer their young overweight or obese patients to structured behavioural inventions such as working with nutritionists and other professionals.

Oliver said it is cheaper in the long term and ultimately more effective to target children in schools, with a mandatory curriculum that teaches them how to raise a garden, cook food, and learn "about geography, the history, the science, the maths behind it all."

"Compulsory food education for every Canadian kid has not been promised, and that to me is immoral," said Oliver.

"It's time for the Canadian government to draw a line in the sand and say we need to support teachers. When kids come to school with no breakfasts ... when the food in lunch boxes is inappropriate, this is not helping teachers do their jobs."

Oliver said he finds Canadians to be generally better educated about food issues than people in other countries, so he said they should "not ask, but tell" their politicians to do more.

That's one reason why he said he partnered with Nova Scotia-based supermarket chain Sobeys two years ago to bring healthy food options to consumers.

The UN Special Rapporteur on Food, Oliver de Shutter, tried offering some advice to the Harper government in 2013 when he called for a national food strategy to deal with what he saw as nutritional inequities.

In response, then health minister Leona Aglukkaq called De Schutter "ill-informed" and "patronizing" while former immigration minister Jason Kenney described him as "completely ridiculous."